New silicone resin for water-repellent wood coatings and binders for exterior paints

The Munich-based Wacker Group has announced that it is is presenting new binders and additives for the paint and surface-coating industries at the European Coatings Show (ECS) in Nuremberg, Germany, from April 21 to 23, 2015. One of the highlights is the new silicone resin emulsion Silres WH. The product, which is based on a new silicone resin can be used as a hydrophobising wood impregnating agent or as an additive in wood stains. Wood impregnated with Silres WH is protected against damp, moisture and the subsequent damage caused by fungi and insects for an exceedingly long time. Wackeris also showcasing a binder from its new Primis line for high-value outdoor applications. Primis AF 1000, the line’s first product, combines organic and inorganic components, enabling the for mulation of bright, highly durable, exterior paints with reduced dirt pick-up.

At ECS 2015, WACKER will be premiering a silicone resin emulsion for wood protection coatings. Its superior impregnating effect enables long-term protection against damp, moisture and damage from moisture exposure. Marketed as Silres WH, the product is so flexible that it even bonds to wood surfaces and, thus, retains the hydrophobic, ie water-repellent properties typical for silicones for many years. Long-term tests with impregnated wood show that the moisture and damp resistant properties of Silres WH are fully intact after 15 years. Silicone resin additives, which have been successfully used on mineral substrates for decades can now provide wood with lasting outdoor protection.

The 50% emulsion is based on a functional silicone resin and is suitable as a wood impregnant or as an additive for formulating film-forming, pigmented wood stains. Due to its hydrophobic properties, Silres WH significantly reduces the water uptake of wood and, as a result, its moisture content. Weathering tests have shown that the silicone resin’s impregnating effect lasts for many years. Thus, wood is better protected against typical damage caused, for example, by fungi, mould and insects or by cracks due to shrinkage and swelling. It is possible to reduce the use of biocides in formulations significantly. In wood stains and coatings, even low amounts of Silres WH provide a long- lasting hydrophobic effect.

Silres WH produces a visible beading effect on wood surfaces. By providing wood with long-term protection, the product greatly reduces the frequency of renovation and recoating compared with conventional wood preservatives. Best results are achieved when mixing the additive with water in a 1:4 to 1:9 ratio. In water-based stains, a concentration of up to three percent Silres WH is sufficient.

Less dirt and more colour: Primis AF 1000

A further ECS 2015 highlight is the new Primis line, comprising binders and additives for advanced, high-value paints and architectural coatings. The new line combines organic and mineral components to deliver a binder with a completely novel property profile. The elastic, acrylic ester-based, organic component performs a binder’s traditional role, offering strong adhesion and cohesion, good mechanical properties and enhanced processability. The solid mineral components, on the other hand, have outstanding protective properties and ensure long-lasting, bright colours and reduced dirt pick-up.

Primis AF 1000 offers improved scratch and abrasion resistance, optimised thermal conductivity and water-vapour permeability and simpler and more even processing. Additionally, the dispersion is characterised by excellent film formation, even at low outdoor temperatures and by its elasticity, while its surface exhibits maximum blocking resistance. The mineral components also improve fire performance. The dispersion’s good pigment compatibility and colour consistency keep exterior paints bright for longer – extending renovation cycles and, in turn, positively impacting overall costs.

Primis AF 1000 dispersion is ideal for challenging exterior applications and expands Wacker’s extensive portfolio designed for plasters and exterior coatings.